Send and receive current debugger mode

Summary:
Make sure mobile client and sonar desktop app keep debugger mode in sync

Desktop client listens to available modes and currently selected mode which is what we use here.

Later we can tweak the logic to try to restore last mode if desktop or mobile clients crash / disconnect etc

Reviewed By: lblasa

Differential Revision: D49384358

fbshipit-source-id: 5bc1f4240253b68a746dfa5feba4b352f4e261a2

iOS/Plugins/FlipperKitUIDebuggerPlugin/FlipperKitUIDebuggerPlugin/Serializers/UIDInitEvent+Foundation.m

@@ -9,6 +9,7 @@
 
 #import "NSArray+Foundation.h"
 #import "UIDInitEvent+Foundation.h"
+#import "UIDTraversalMode.h"
 
 FB_LINKABLE(UIDInitEvent_Foundation)
 @implementation UIDInitEvent (Foundation)
@@ -19,6 +20,12 @@ FB_LINKABLE(UIDInitEvent_Foundation)
     @"frameworkEventMetadata" : self.frameworkEventMetadata
         ? [self.frameworkEventMetadata toFoundation]
         : @[],
+    @"supportedTraversalModes" : @[
+      NSStringFromUIDTraversalMode(UIDTraversalModeViewHierarchy),
+      NSStringFromUIDTraversalMode(UIDTraversalModeAccessibilityHierarchy),
+    ],
+    @"currentTraversalMode" :
+        NSStringFromUIDTraversalMode(self.currentTraversalMode),
   };
 }